Method for continuous warp dyeing polyester and blends of polyester on conventional pad-steam dye slasher

ABSTRACT

A process for continuous dyeing polyester yarns is disclosed, wherein the yarns are dyed on a pad-steam dye slasher with a disperse dye solution. The disperse dye solution contains a disperse dyestuff, an at most somewhat water-miscible unemulsified, halogenated aromatic solvent, an anionic wetting agent and a thickener, with the anionic wetting agent added to the disperse dye solution after the aqueous system of disperse dyestuff and solvent is formed. The disperse dye is fixed on the yarn by steaming the yarn at a temperature of at least 220*F. The disclosed process is useful in the disperse dyeing of polyester yarns which may be used in conventional applications for such yarns.

United States Patent 1 Finch et al.

[ July 8,1975

[ METHOD FOR CONTINUOUS WARP DYEING POLYESTER AND BLENDS OF POLYESTER ON CONVENTIONAL PAD-STEAM DYE SLASHER [75] Inventors: Wilton C. Finch; David C. Eller,

both of Burlington, NC.

[73] Assignee: Burlington Industries, Inc.,

Greensboro, NC.

[22] Filed: Jan. 19, 1973 [21] Appl. No.: 325,035

[52] US. Cl. 8/174; 8/179; 8/DIG. 4;

[51] Int. Cl D06p l/68 [58] Field of Search 8/174, 179, 94, DIG. 4

[56] References Cited UNITED STATES PATENTS 3,084,015 4/1963 Grossmann et al. 8/174 X 3,164,436 l/l965 Altermatt et a1. 8/174 X 3,313,590 4/1967 Delano et a1. 8/174 X 3,512,913 5/1970 Day et al. 8/92 X 3,541,024 11/1970 Weisz et a1. 8/174 X 2/1972 McCollough et a1. 8/174 X 2/1974 Guenthner 8/174 X Primary Examiner Benjamin R. Padgett Assistant Examinef--P. A. Nelson Attorney, Agent, 0r Firm-Cushman, Darby & Cushman 5 7] ABSTRACT The disclosed process is useful in the disperse dyeing of polyester yarns which may be used in conventional applications for such yarns.

13 Claims, No Drawings METHOD FOR CONTINUOUS WARP DYEING POLYESTER AND BLENDS OF POLYESTER ON CONVENTIONAL PAD-STEAM DYE SLASHER BACKGROUND OF THE INVENTION The prior art has encountered substantial difficulties in the pad disperse dyeing of polyester yarns, as the only previous method of obtaining adequate disperse dye fixation in reasonable periods of time for continuous production involves thermosoling the padding yarns at temperatures in the range of 400 425F. Such a temperature fixation procedure is undesirable, both from the economic viewpoint and because the elevated temperatures may result in degradation of the fiber and/or dyestuffs especially when equipment is slowed because of broken fibers.

The Merian et al US. Pat. No. 3,042,478 discloses a process for dyeing polyester fibers with a specific class of disperse dyestuffs. The patentees disclose that dispersing agents and thickening agents may be added to the dye bath. The patent discloses, for instance, padding a Dacron fabric with an aqueous dye composition containing a dispersing agent and a thickening agent. with dyestuff fixation by steaming the padded fabric for about 5 minutes at 120C and 1.2 atmospheres. Such extended steaming times render such an approach commercially unfeasible for the continuous dyeing of polyester yarn.

DESCRIPTION OF THE INVENTION The present invention is directed to the continuous warp dyeing of polyester yarns or other yarns on a padsteam dye slasher. The process provides a ready method of warp dyeing polyester yarns without necessitating the use of the high temperatures or thermosoling required by prior art processes, and thus represents a substantial advance in the art.

The dye bath is an aqueous system which contains a solvent, an emulsifier, disperse dyestuffs, and a thickener, mixed in a certain order of addition. The dye bath composition is padded onto polyester yarns, and then the polyester yarn is subjected to a steaming or other heating step to fix the dyestuff. The dyeing operation is conducted on a pad-steam dye slasher.

The solvent is suitably a halogenated, preferably chlorinated. unemulsified aromatic compound containing at least 6 carbon atoms, such as, for instance, 1,2,4- trichlorobenzene or the like. The solvent must be a solvent for the disperse dyestuff (the dyestuff should be at least 90 percent soluble in the solvent), and should also be at most only somewhat water-miscible. That is, the solvent should be soluble at most to the extent of 10% by weight in water at room temperature, before emulsification. In addition, the solvent should have a medium to high volatility in steam. This latter requirement is generally satisfied if the solvent has a vapor pressure of at least 100 mmHg at 212F. There is no absolute upper limit of the number of carbon atoms which the solvent can contain, as long as the above criteria are satisfied, but normally the solvent will have no more than 12 carbon atoms or so.

l.2.4-trichlorobenzene is normally sold in the emulsifled form. It might be expected that this emulsified 1,2.4-trichlorobenzene. or other emulsified solvent, would function as well or even better in the process of the present invention, but it has been unexpectedly found that the dye yield is considerably decreased if the solvent contains emulsifier. For this reason, it is highly significant to the successful practice of the process of the present invention that the solvent be used in an unemulsified form. Generally, at least 5 ounces per gallon of dye bath of the solvent will be used, and up to 30 or 35 or even more ounces per gallon of the solvent may be used. Preferably, the solvent will be used in an amount of from about 15 to 30 ounces per gallon.

The emulsifier is an anionic wetting agent or surfactant, preferably of the anionic alkylaryl polyether alcohol sulfonate and sulfate type, more preferably of the sulfonated ester type, such as dioctyl sodium sulfosuccinate, sodium dinaphthylemethane disulfonate, soap, sulfite waste liquor residue, sodium cetylsulfate, and the like. The emulsifier is used in an amount of from about 0.2 to l or more ounces per gallon, preferably about 0.6 ounces per gallon of dye bath.

The disperse dyestuff can be any conventional disperse dyestuff, as long as the dyestuff is at least 90 percent soluble in the particular solvent used. Suitable disperse dyestuffs are described in the Technical Manual of the American Association of Textile Chemists and Colorists, 1961, Howes Publishing Co. NYC, pp 205-279 and 292-293, the disclosure of which is hereby incorporated by reference. Generally, the dyestuff will be used in an amount of from 0.5 to 5.0 ounces per gallon of dye bath, as at levels above about 5 ounces per gallon additional dyestuff cannot generally be placed on the fiber. However, it is clear that the dyebath could actually contain more dyestuff, e.g., as much as 20 ounces per gallon or even more, but no advantage would result from such high amounts of disperse dyestuff.

The thickener can be any of the conventional thickening agents known to the art, but quite good results I have been obtained with carboxymethylcellulose. Other suitable thickeners, besides carboxymethylcellulose, are carboxyethylcellulose and alkaliswellable acrylic polymers and copolymers, including thermosetting acrylic emulsions sold by Rohm and Haas under the trade name Rhoplex A-4 l and AC- 201, alkali-swellable acrylic emulsion copolymers, such as those sold by Rohm and Haas under the trade names Acrysol ASE-", ASE- and ASE-, and acrylic acid polymers such as those sold by Polymer Industries under the trade names TF-30 and Polyfilm, as well as Polymer Industries"Polythickener", an ethylpolyacrylate, as well as viscous solutions of polyvinylacetate such as those sold by Monsanto under the Gelva trade name. Furthermore, alkali-swellable polyvinylalcohols, such as those products sold by Monsanto under the trade name Gelvatol", may also be used as thickeners in the process of the present invention. The natural gum derivative thickening agents generally do not perform as well because of build-up problems on the processing equipment.

The thickener will be present in an amount of at least one ounce per gallon and may be used in amounts as high as 8.0 ounces per gallon or even higher, as long as the thickened dyebath is pourable. Preferably, the thickenerwill be used in an amount of about 3.0 to 7.0 ounces per gallon, most preferably about 5.0 ounces per gallon. The thickener is required in order to achieve an adequate pickup of the dyestuffs by the yarns, and to prevent disperse dyestuff precipitation from the dyebath as well as to assist in forming a stable emulsion.

Other examples of suitable emulsifiers, thickeners, and solvents will be found in the 1961 AATCC Technical Manual, identified above, at pages 357-358 and 36937l, the disclosure of which is hereby incorporated by reference for the additional teachings of these dyebath ingredients. The bath may also contain various other additives conventionally used in the dyeing art. For example, monosodium phosphate may be used as a bath stabilizer or buffer for pH control.

In forming the dye bath, it is critical to form an aqueous system of disperse dyestuff and solvent prior to adding the emulsifier. The thickener may be added at any convenient point, but is preferably added after the emulsifier has been incorporated in the dye bath system.

The dye bath is padded on a pad-steam dye slasher on polyester yarns. The dye bath, of course, may be applied to other types of yarns, such as nylon or acetate yarns, but the significant advantages of the present invention reside in the dyeing of polyester warps, wherein the prior art required high temperature fixation or thermosoling. The dispersed dye system is applied to the polyester yarns by padding with a dye bath pick-up in the amount of about 50 to 70 percent by weight, although higher amounts of dye system may be applied. Preferably, the amount of disperse dye system applied to the polyester yarn will be about 60 to 65 percent by weight as the yarn comes out of the bath. The pick-up of the dye system by the polyester yarns may be accomplished by various conventional dyeing techniques although padding is decidedly preferred. Generally, when padding is used the pad nip pressure will be in the range of 1000-1500 pounds/inch, preferably about 1200 pounds/inch.

The polyester yarn containing the dye system thereon is then steamed at a temperature of 220 to 250F for 20 or 40 seconds or more and until the dyestuff-solvent emulsion is broken and the dye is on the fiber. Higher temperatures can be used, e.g., as high as even 400 to 45 F, with a resulting shorter heating time, but no particular advantage is gained thereby and, in fact, the low temperature continuous dyeing of polyester yarn is particularly preferred, with quite uniform dyeing results obtained thereby.

EXAMPLES OF THE INVENTION EXAMPLE 1 An aqueous dye solution was made by mixing in order, 20 oz. per gallon of 1,2,4-trichlorobenzene, 3.0 oz. per gallon Polynal Blue GLF, 0.6 oz. per gallon of Triton GR-S (dioctyl sodium sulfosuccinate), and 0.25 oz.-

per gallon of monosodiumphosphate.

A carboxymethyl cellulose (CMC) solution was formed by mixing 50 lbs. of CMC in 50 gallons of water. Two gallons of this CMC solution were added to 8 gallons of the dye solution to form a thickened dye solution or dye bath.

The resulting thickened dye solution was placed in the box of a conventional dye slasher. l40 den., 27 fil., R02 polyester was added at 1200 pounds/in. with the dye solution in the slasher dye box and then steamed at a temperature of 220F. for about 30 seconds.

The resulting dyed polyester yarns had a good buildup of shade, with some slight streaking.

EXAMPLE 2 Example 1 was repeated, except 200 grams of Acrysol ASE-60, an alkali-swellable acrylic copolymer emulsion, was added to 10 gallons of the disperse dye bath solution. The levelness of the dye was improved (the streaking was eliminated) but the dye shade was slightly weaker.

EXAMPLE 3 Example 2 was repeated, except 2 additional gallons of the CMC solution described in Example I were added to 10 gallons of the disperse dye bath solution. Although the dye solution was diluted 20%, the resulting dyed polyester had a decidedly heavier dye shade, indicating an improved dye pickup by the yarn.

EXAMPLE 4 An aqueous disperse dye bath solution was produced by mixing, in order, 20 oz. per gallon of 1,2,4- trichlorobenzene, 3.2 oz. per gallon of Latyl Yellow GFSW, 0.6 oz. per gallon of Triton GR-S and 0.25 oz. per gallon of monosodium phosphate. To this emulsified mix 200 grams of Acrysol ASE-60 were added and then 3 lbs. of CMC, previously dissolved in water, were added, to form a l0 gallon solution.

This disperse dye solution was used to dye a 140 den., 27 fil., R02 polyester on a conventional slasher, using the procedure described in Example 1, with the dye solution placed in the dye box. The viscosity of the dye solution appeared quite favorable, being thick but such that the solution would still flow through the dye lines on the slasher. The polyester was dyed a heavy shade of bright yellow which passed all upholstery physical tests.

EXAMPLE 5 Example 4 was repeated, substituting Polynal Blue GNF for the yellow dye of the previous example, and was used to dye a similar polyester with similar results, although this solution had a tendency to stick to the rolls.

EXAMPLE 6 550 Grams of Polynal Gold Yellow 3RL, 300 grams of Latyl Yellow GSFW (Dispersed Yellow 67) and 10 grams of Polynal Blue GSF (Dispersed Blue 27) were stirred into 5,780 grams of 1,2,4-trichlorobenzene. 7l Grams of monosodium phosphate and 170 grams of Triton GR-S were added to the dye solution, along with an amount of water to make a final mix of 10 gallons. The resulting emulsified solution was added to a mix tank along with grams of Acrysol ASE-60 and 2,724 grams of CMC.

The resulting disperse dye solution was added to the dye box of a pad-steam dye slasher and used to dye den., 27 fil., R02 polyester, using the procedure of Example l.

EXAMPLE 7 Example 6 was repeated. with the disperse dye solution ingredients mixed in the same order as Example 6 using the following ingredients to form a gallon mix:

I 1.560 grams 1.2.4-trichlorobenzenc l.l00 grams Latyl Yellow GSFW (Dispcrsc Yellow 67) 200 grams Polynal Gold Yellow 3RL 20 grams Polynal Blue GLF (Dispersc Blue 27) 340 grams Triton GR-S 145 grams Monosodium phosphate 200 grams Acrysol ASE-60 2.724 grams (MC q.s. water 600 yards of I40 den., 27 fil., R02 polyester were dyed with the above dispersed dye solution at a speed of 20 yards per minute on a pad steam dye slasher, using a steam temperature of 220F for seconds. Very little bleed was observed in the dye box. The resulting polyester had a slightly reddish-gold shade.

EXAMPLE 8 EXAMPLE 9 Example 7 was repeated, using the following ingredients to form a l0 gallon mix:

5.780 grams l.2,4 Trichlorobcnzcne 850 grams Latyl Yellow GPSW (Disperse Yellow 67) 75 grams Polynal Blue GLF (Disperse Blue 27) I70 grams Triton GR-S 70 grams Monosodium phosphate 100 grams Polygum L (a natural gum ether sold by Polymer Corporation) q.s. water 140 den., 27 fil., R02 polyester was dyed with the above dye solution, using the same equipment and dyeing conditions as in Example 7. The resulting polyester had a heavy green shade, and the overall results were quite successful.

What is claimed is:

1. A process for the continuous dyeing of polyester yarns, said process comprising first forming a disperse dye solution by admixing water, 0.5 to 5 oz. of at least one disperse dye per gallon of solution, and 5 to 35 oz. per gallon of solution of at least one at most somewhat water miscible, unemulsified, halogenated aromatic compound containing at least 6 carbon atoms which is a solvent for said disperse dye and which is soluble in water at room temperature before emulsification at most to the extent of about 10% by weight, and thereafter adding 0.2 to 1 oz. per gallon of solution of an anionic wetting agent per gallon of water, adding at least 1 oz. per gallon of solution of a thickener, thereafter applying said disperse dye solution to polyester yarns on a steam-pad dye slasher in an amount of at least 50 percent by weight of the yarn, and fixing the disperse dye upon said yarn by steaming the yarn to a temperature of at least 220F. until the dye is fixed on the yarn.

2. Process as claimed in claim 1, wherein said thickener is selected from the group consisting of carboxymethyl cellulose and alkali-swellable acrylic copolymers.

3. Process according to claim 2, wherein said thickener is used in an amount of about 3 7 ounces per gallon of dye solution.

4. Process according to claim 1, wherein said solvent has a vapor pressure of at least mmHg at 212F.

5. Process according to claim 4, wherein said solvent is 1,2,4-trichlorobenzene.

6. Process according to claim 4, wherein said solvent is used in an amount of from about 15 to about 30 ounces per gallon of dye solution.

7. Process according to claim 1, wherein said wetting agent is a sulfonated ester type of wetting agent.

8. Process according to claim 7, wherein about 0.6 ounces of wetting agent are used per gallon of dye bath.

9. Process according to claim 1, wherein from 60 65% by weight of said dye solution is applied to said yarns, based on the weight of the yarn.

10. Process according to claim 1, wherein the dye is fixed on the yarn by steaming the yarn at a temperature of 220 450F.

11. Process according to claim 1, wherein said thickener is added before the addition of said wetting agent.

12. Process according to claim 1, wherein said thickener is added with said wetting agent.

13. Process according to claim 1, wherein said thickener is added after the addition of said wetting agent. 

1. A PROCESS FOR THE CONTINUOUS DYEING OF POLYESTER YARNS. SAID PROCESS COMPRISING FIRST FORMING A DISPERSE DYE SOLUTION BY ADMIXING WATER, 0.5 TO 5 OZ. OF AT LEAST ONE DISPERSE DYE PER GALLON OF SOLUTION, AND 5 TO 35 OZ PER GALLON OF SOLUTION OF AT LEAST ONE AT MOST SOMEWHAT WATER MISCIBLE, UNEMULSIFIED, HALOGENATED AROMATIC COMPOUND CONTAINING AT LEAST 6 CARBON ATOMS WHICH IS A SOLVENT FOR SAID DISPERSE DYE AND WHICH IS SOLUBLE IN WATER AT ROOM TEMPERATURE BEFORE EMULSIFICATION AT MOST TO THE EXTENT OF ABOUT 10% BY WEIGHT, AND THEREAFTER ADDING 0.2 TO 1 OZ PER GALLON OF AN ANIONIC WETTING AGENT PER GALLON OF WATER, ADDING AT LEAST 1 OZ. PER GALLON OF SOLUTION OF A THICKENER, THEREAFTER APPLYING SAID DISPERSE DYE SOLUTION TO POLYESTER YARNS ON A STEAM-PAD DYE SLASHER IN AN AMOUNT OF AT LEAST 50 PERCENT BY WEIGHT OF THE YARN, AND FIXING THE DISPERSE DYE UPON SAID YARN BY STEAMING THE YARN TO A TEMPERATURE OF AT LEAST 220*F. UNTIL THE DYE IS FIXED ON THE YARN.
 2. Process as claimed in claim 1, wherein said thickener is selected from the group consisting of carboxymethyl cellulose and alkali-swellable acrylic copolymers.
 3. Process according to claim 2, wherein said thickener is used in an amount of about 3 - 7 ounces per gallon of dye solution.
 4. Process according to claim 1, wherein said solvent has a vapor pressure of at least 100 mmHg at 212*F.
 5. Process according to claim 4, wherein said solvent is 1,2,4-trichlorobenzene.
 6. Process according to claim 4, wherein said solvent is used in an amount of from about 15 to about 30 ounces per gallon of dye solution.
 7. Process according to claim 1, wherein said wetting agent is a sulfonated ester type of wetting agent.
 8. Process according to claim 7, wherein about 0.6 ounces of wetting agent are used per gallon of dye bath.
 9. Process according to claim 1, wherein from 60 - 65% by weight of said dye solution is applied to said yarns, based on the weight of the yarn.
 10. Process according to claim 1, wherein the dye is fixed on the yarn by steaming the yarn at a temperature of 220* - 450*F.
 11. Process according to claim 1, wherein said thickener is added before the addition of said wetting agent.
 12. Process according to claim 1, wherein said thickener is added with said wetting agent.
 13. Process according to claim 1, wherein said thickener is added after the addition of said wetting agent. 